Verify the scenarios when d.ts directory of dependency doesnt exist

src/compiler/program.ts

@@ -826,8 +826,11 @@ namespace ts {
                 if (!resolvedProjectReferences) {
                     resolvedProjectReferences = projectReferences.map(parseProjectReferenceConfigFile);
                 }
-                if (host.setGetSourceOfProjectReferenceRedirect) {
-                    host.setGetSourceOfProjectReferenceRedirect(getSourceOfProjectReferenceRedirect);
+                if (host.setResolvedProjectReferenceCallbacks) {
+                    host.setResolvedProjectReferenceCallbacks({
+                        getSourceOfProjectReferenceRedirect,
+                        forEachResolvedProjectReference
+                    });
                 }
                 if (rootNames.length) {
                     for (const parsedRef of resolvedProjectReferences) {
@@ -1226,8 +1229,11 @@ namespace ts {
             }
             if (projectReferences) {
                 resolvedProjectReferences = projectReferences.map(parseProjectReferenceConfigFile);
-                if (host.setGetSourceOfProjectReferenceRedirect) {
-                    host.setGetSourceOfProjectReferenceRedirect(getSourceOfProjectReferenceRedirect);
+                if (host.setResolvedProjectReferenceCallbacks) {
+                    host.setResolvedProjectReferenceCallbacks({
+                        getSourceOfProjectReferenceRedirect,
+                        forEachResolvedProjectReference
+                    });
                 }
             }
 

src/compiler/types.ts

@@ -5166,7 +5166,7 @@ namespace ts {
         /* @internal */ hasChangedAutomaticTypeDirectiveNames?: boolean;
         createHash?(data: string): string;
         getParsedCommandLine?(fileName: string): ParsedCommandLine | undefined;
-        /* @internal */ setGetSourceOfProjectReferenceRedirect?(getSource: GetSourceOfProjectReferenceRedirect): void;
+        /* @internal */ setResolvedProjectReferenceCallbacks?(callbacks: ResolvedProjectReferenceCallbacks): void;
         /* @internal */ useSourceInsteadOfReferenceRedirect?(): boolean;
 
         // TODO: later handle this in better way in builder host instead once the api for tsbuild finalizes and doesn't use compilerHost as base
@@ -5175,10 +5175,13 @@ namespace ts {
 
     /** true if --out otherwise source file name */
     /*@internal*/
-    export type SourceOfProjectReferenceRedirect = string | true ;
+    export type SourceOfProjectReferenceRedirect = string | true;
 
     /*@internal*/
-    export type GetSourceOfProjectReferenceRedirect = (fileName: string) => SourceOfProjectReferenceRedirect | undefined;
+    interface ResolvedProjectReferenceCallbacks {
+        getSourceOfProjectReferenceRedirect(fileName: string): SourceOfProjectReferenceRedirect | undefined;
+        forEachResolvedProjectReference<T>(cb: (resolvedProjectReference: ResolvedProjectReference | undefined, resolvedProjectReferencePath: Path) => T | undefined): T | undefined;
+    }
 
     /* @internal */
     export const enum TransformFlags {

src/server/project.ts

@@ -1482,7 +1482,8 @@ namespace ts.server {
         configFileWatcher: FileWatcher | undefined;
         private directoriesWatchedForWildcards: Map<WildcardDirectoryWatcher> | undefined;
         readonly canonicalConfigFilePath: NormalizedPath;
-        private getSourceOfProjectReferenceRedirect: GetSourceOfProjectReferenceRedirect | undefined;
+        private projectReferenceCallbacks: ResolvedProjectReferenceCallbacks | undefined;
+        private mapOfDeclarationDirectories: Map<true> | undefined;
 
         /* @internal */
         pendingReload: ConfigFileProgramReloadLevel | undefined;
@@ -1529,8 +1530,8 @@ namespace ts.server {
         }
 
         /* @internal */
-        setGetSourceOfProjectReferenceRedirect(getSource: GetSourceOfProjectReferenceRedirect) {
-            this.getSourceOfProjectReferenceRedirect = getSource;
+        setResolvedProjectReferenceCallbacks(projectReferenceCallbacks: ResolvedProjectReferenceCallbacks) {
+            this.projectReferenceCallbacks = projectReferenceCallbacks;
         }
 
         /* @internal */
@@ -1538,13 +1539,42 @@ namespace ts.server {
 
         fileExists(file: string): boolean {
             // Project references go to source file instead of .d.ts file
-            if (this.languageServiceEnabled && this.getSourceOfProjectReferenceRedirect) {
-                const source = this.getSourceOfProjectReferenceRedirect(file);
+            if (this.useSourceInsteadOfReferenceRedirect() && this.projectReferenceCallbacks) {
+                const source = this.projectReferenceCallbacks.getSourceOfProjectReferenceRedirect(file);
                 if (source) return isString(source) ? super.fileExists(source) : true;
             }
             return super.fileExists(file);
         }
 
+        directoryExists(path: string): boolean {
+            if (super.directoryExists(path)) return true;
+            if (!this.useSourceInsteadOfReferenceRedirect() || !this.projectReferenceCallbacks) return false;
+
+            if (!this.mapOfDeclarationDirectories) {
+                this.mapOfDeclarationDirectories = createMap();
+                this.projectReferenceCallbacks.forEachResolvedProjectReference(ref => {
+                    if (!ref) return;
+                    const out = ref.commandLine.options.outFile || ref.commandLine.options.outDir;
+                    if (out) {
+                        this.mapOfDeclarationDirectories!.set(getDirectoryPath(this.toPath(out)), true);
+                    }
+                    else {
+                        // Set declaration's in different locations only, if they are next to source the directory present doesnt change
+                        const declarationDir = ref.commandLine.options.declarationDir || ref.commandLine.options.outDir;
+                        if (declarationDir) {
+                            this.mapOfDeclarationDirectories!.set(this.toPath(declarationDir), true);
+                        }
+                    }
+                });
+            }
+            const dirPath = this.toPath(path);
+            const dirPathWithTrailingDirectorySeparator = `${dirPath}${directorySeparator}`;
+            return !!forEachKey(
+                this.mapOfDeclarationDirectories,
+                declDirPath => dirPath === declDirPath || startsWith(declDirPath, dirPathWithTrailingDirectorySeparator)
+            );
+        }
+
         /**
          * If the project has reload from disk pending, it reloads (and then updates graph as part of that) instead of just updating the graph
          * @returns: true if set of files in the project stays the same and false - otherwise.
@@ -1553,6 +1583,8 @@ namespace ts.server {
             this.isInitialLoadPending = returnFalse;
             const reloadLevel = this.pendingReload;
             this.pendingReload = ConfigFileProgramReloadLevel.None;
+            this.projectReferenceCallbacks = undefined;
+            this.mapOfDeclarationDirectories = undefined;
             let result: boolean;
             switch (reloadLevel) {
                 case ConfigFileProgramReloadLevel.Partial:
@@ -1567,7 +1599,6 @@ namespace ts.server {
                 default:
                     result = super.updateGraph();
             }
-            this.getSourceOfProjectReferenceRedirect = undefined;
             this.projectService.sendProjectLoadingFinishEvent(this);
             this.projectService.sendProjectTelemetry(this);
             return result;
@@ -1684,6 +1715,8 @@ namespace ts.server {
             this.stopWatchingWildCards();
             this.projectErrors = undefined;
             this.configFileSpecs = undefined;
+            this.projectReferenceCallbacks = undefined;
+            this.mapOfDeclarationDirectories = undefined;
             super.close();
         }
 

src/services/services.ts

@@ -1246,8 +1246,8 @@ namespace ts {
                     return host.resolveTypeReferenceDirectives!(typeReferenceDirectiveNames, containingFile, redirectedReference);
                 };
             }
-            if (host.setGetSourceOfProjectReferenceRedirect) {
-                compilerHost.setGetSourceOfProjectReferenceRedirect = getSource => host.setGetSourceOfProjectReferenceRedirect!(getSource);
+            if (host.setResolvedProjectReferenceCallbacks) {
+                compilerHost.setResolvedProjectReferenceCallbacks = callbacks => host.setResolvedProjectReferenceCallbacks!(callbacks);
             }
             if (host.useSourceInsteadOfReferenceRedirect) {
                 compilerHost.useSourceInsteadOfReferenceRedirect = () => host.useSourceInsteadOfReferenceRedirect!();

src/services/types.ts

@@ -237,7 +237,7 @@ namespace ts {
         /* @internal */
         getSourceFileLike?(fileName: string): SourceFileLike | undefined;
         /* @internal */
-        setGetSourceOfProjectReferenceRedirect?(getSource: GetSourceOfProjectReferenceRedirect): void;
+        setResolvedProjectReferenceCallbacks?(callbacks: ResolvedProjectReferenceCallbacks): void;
         /* @internal */
         useSourceInsteadOfReferenceRedirect?(): boolean;
     }

src/testRunner/unittests/tsserver/projectReferences.ts

@@ -727,6 +727,36 @@ ${dependencyTs.content}`);
                         /*afterActionDocumentPositionMapperNotEquals*/ undefined,
                         /*useDepedencyChange*/ true
                     );
+
+                    it("when d.ts file is not generated", () => {
+                        const host = createServerHost(files);
+                        const session = createSession(host);
+                        openFilesForSession([...openFiles, randomFile], session);
+
+                        const expectedClosedInfos = closedInfos.filter(f => f.toLowerCase() !== dtsPath && f.toLowerCase() !== dtsMapPath);
+                        // If closed infos includes dts and dtsMap, watch dts since its not present
+                        const expectedWatchedFiles = closedInfos.length === expectedClosedInfos.length ?
+                            otherWatchedFiles :
+                            otherWatchedFiles.concat(dtsPath);
+                        // Main scenario action
+                        verifyAllFnActionWorker(session, ({ reqName, response, expectedResponse }) => {
+                            assert.deepEqual(response, expectedResponse, `Failed on ${reqName}`);
+                            verifyInfosWithRandom(session, host, openInfos, expectedClosedInfos, expectedWatchedFiles);
+                            verifyDocumentPositionMapper(session, /*dependencyMap*/ undefined, /*documentPositionMapper*/ undefined);
+                        }, /*dtsAbsent*/ true);
+                        checkProject(session);
+
+                        // Collecting at this point retains dependency.d.ts and map
+                        closeFilesForSession([randomFile], session);
+                        openFilesForSession([randomFile], session);
+                        verifyInfosWithRandom(session, host, openInfos, expectedClosedInfos, expectedWatchedFiles);
+                        verifyDocumentPositionMapper(session, /*dependencyMap*/ undefined, /*documentPositionMapper*/ undefined);
+
+                        // Closing open file, removes dependencies too
+                        closeFilesForSession([...openFiles, randomFile], session);
+                        openFilesForSession([randomFile], session);
+                        verifyOnlyRandomInfos(session, host);
+                    });
                 }
             }